Method of heating material at successively different temperatures



Jan. 5 ,1926. 1,568,886

' A. MOD. DUCKHAM ET AL METHOD 0: HEATING MATERIAL AT SUCQESSIVELYDIFFERENT TEMPERATURES v v 1 3w Q m .mww wfi, 1 a 4 Mg g MT mfim H. P.-mw U mHH- M a .N g

1 l I I I l l I r l I I I I l IL Jan. 5', 1928; 1,568,886

A. M D. DUCKHAM ET AL METHOD OF HEATING MATERIAL AT SUdCESSIVELYDIFFERENT TEMPERATURES Filed August 9, 1921 I 2 Sheets-Sheet 2 atented5, 1923.

ARTHUR HoDOUGALL ncem.

AND J srsniinr measure, or Lennon, sne- LAND, ALMIGHO RS '1'0 THERMALINDUSTRIAL ND CHEMICAL (T. I. C.) RESEARCH cousin LEKITED, OF LONDON,ENGLAND,;A BRIQISH COMIANY.

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To all? whom. it may concem:

Be it hnownthat we, McDouesm. Doorman: and Jenn STANLEY MORGAN, bothsubjects of the King of Great Britain, ti residing in London, England,have jointly invented a certain new and useful Improved Method ofHeating Material at Successively Different Temperatures, of which thefollowing is a specification.

A known process of subjecting a mute rial to heat treatment by contact wth a molten metal ($...5l8i38 in causin 1 rial to travel between asurface of the molten metal and a solid surface wholly or 15 partlysubmerged in the molten metal. Sometimes the solid surface travels withthe material, as when the material is caused.

to enter the re-entrant angle between the surface of the metal and thesurface of a M drum revolving partly submerged 1n the I molten metal.Sometimes the wlid surface is stationary and inclined, so that thematerial, introduced beneath the lower end of the surface, travelsupwards along the surface owing to the fact that the material sspecifically lighter than the molten metal. By the present inventionheat treatment of the material is conducted in successive steps bycausin the material to travel repeatedly throng molten metal as abovedescribed and to acquire a difl'erent temperature ateach passage.

When a. single bath of molten metal is used and the successivetemperature steps are attained by varying the time durln which thetravel .occurs, the time of trave in each stage wherein the temperatureto be attained is lower than the tem erature of the molten metal, mustbeinsu cient to permit the material to attain the temperature of themolten metal, and must be adjusted so that it is onl sufficient toperimit the material to attain the desired'temperature. l

The invention is illustrated in the accompanying drawings.

Fig. 1 .is a longitudinah sect1on through a number of stills arrangedfor the fractional distillation of tar oil. The form of still has beendescribed in the application for United States Letters Patent of John S.Morgan, Serial No. 490,650.

Fig. 2 is a plan and Fig. 3 a cross-section of Fig. 1.

are set in the flue of a furnace b.

the mate- Application flied new a, 1am. Serial in. 493,021.

Fig. 4 is a view similar to Fig. 1 ofa modification, and in plan itresembles Fig. 2. i

Referring to Figs. 1 to 3, the stills a This flue is divided into anupper and lower fine by a partition 0 and there isa lay-pass flue (2putting the upper and'lower flue into communication with each other atoneend of each still. 'The upper flue alone conimunicutes with thefurnace so that the proportion of heating gases passing along the lowerflue is determined by the degree to which the valves c in the upper fluein front of each flue a? are open. It will be seen that by suitableadjustment of these valves and of the corresponding valves f in thelower flue, the temperature of the several stills may be varied.

The oil is fed by pipe 9 into the still furthest from the furnace (andtherefore at the lowest temperature) and is carried beneath the surfaceof the molten lead It by the revolving drum 5. It leaves the still bypipe is to flow to the next still, and so on throughout the series, theresidue being discharged by pipe Z. The volatile conall, serving thefunction of a bottom to each still. In other respects the stills areconstructed as already described and the tar oil flows through them inthe manner al ready described. Each of the cylinders 1', however, isrotated at a different speed, the speed decreasing from one end of theseries om the necks m in well-lmown to the other and being most rapid inthe end still into which the oil is fed and from which the constituentsof lowest boiling, point are collected.

Since all the stills are at the same temperature thelead bath is setdirectly in the flue n of the burner The rate of rotation of each drumor cylinder is such that, in each stage, the

time during which the material passes be tween the surface of thedrumand the molten metal is only sufficient to permit the material toattain the temperature desired l'orthat stage.

The invention is particularly suitable for fractional distillationwhether of liquid or solid material. As an example of the latter thedestructive distillation of Wood may he mentioned, there beingconsiderable adantage in heating the wood in successive stages forobtaining the best yield of the several products.

Having thus described the nature of the said invention and the bestmeans we know of carrying the same into practical efi'ect, we claim:

l. A process of heating a material at successively differenttemperatures for the purpose of fraetionally vaporizing constituentsthereof, which consists in causing the material to travel between asolid surface immersed in a bath of molten metal and a surface of themolten metal, removing the constituents volatilized by the treatment,

and causing the unvolatilized portions of the material to travel betweenanother such solid surface and a surface of molten metal and to acquirea different temperature at each passage.

A process of heating a material at successively difierent temperaturesfor the purpose of fractionally vaporizing constituents thereof, whichconsists in causing the material to travel in a bath of molten metalhaving a given temperature, between a solid surface immersed in saidbath and a surface of the molten metal, removing the constituents"olatilized in the bath, and causing the unrolat-ilized portion of thema terial to pass into another bath of molten metal having another giventemperature and there to travel between another solid surface immersedtherein and a surface of the molten metal.

In testimony whereof we have signed our names to this specification.

ARTHUR McDOUGALL DUCKHAM. JOHN STANLEY MORGAN.

